The core use of trademark protection isn't a commercial use, necessarily. Rather, it's the act of infringing on the trademark holder's commercial use. So, if Waffle House is selling Waffle House t-shirts, and a business next door is giving away free Waffle House t-shirts that they printed - then yes, Waffle House would very likely win a lawsuit against someone giving away waffle house t-shirts.
Basically if someone is giving away or, especially, selling something that causes a confusion against the original trademark, then yes, the trademark "must" be protected.
By "must" I don't mean it's legally required. I just mean you're going to have a harder time in court if you need to pursue legal action against a company or person if there's a precedent you have not actively protected the trademark in other instances.
edit: and in this case, the site was causing confusion, so they sent a C&D. Also as the other commentor mentioned, the logo is trademarked.